This is a complete system to mount the Garmin eTrex Grayscale GPS unit to any handlebar ranging in diameter from 3/4 inch to 1 1/4 inch.  This kit includes the RAM eTrex Grayscale Cradle (NAMT-1-7310), RAM Twist and Lock Suction Mount Base with Ball (NAMT-1-7305), RAM Standard Arm (NAMT-1-7303), and  RAM Diamond Adapter Plate (NAMT-1-7302).  This kit is priced below the total sum of buying the components separately.